Fiberoptic Intubation: An Overview and Updaterc.rcjournal.com/content/respcare/59/6/865.full.pdf · optic intubation (FOI) with a flexible fiberoptic broncho-scope has become a mainstay

Fiberoptic Intubation: An Overview and Update

Stephen R Collins MD and Randal S Blank MD PhD

IntroductionFiberoptic TechnologyIndicationsFiberoptic Techniques

Patient Position and General TechniquesPatient PreparationRegional AnesthesiaSedation Versus General Anesthesia

Combined TechniquesOutcomes/Comparison StudiesComplicationsTraining

SurveysUnited States TrainingCadaversVirtual Simulation and Model Fidelity

Additional UsesSummary

Fiberoptic intubation (FOI) is an effective technique for establishing airway access in patients withboth anticipated and unanticipated difficult airways. First described in the late 1960s, this approachcan facilitate airway management in a variety of clinical scenarios given proper patient preparationand technique. This paper seeks to review the pertinent technology, clinical techniques, and indi-cations for and complications of its use. The role of FOI in airway management algorithms isdiscussed. Evidence is presented comparing FOI to other techniques with regard to difficult airwaymanagement. In addition, we have reviewed the literature on training processes and skill develop-ment in FOI. Key words: fiberoptic bronchoscope (FOB); fiberoptic intubation (FOI); fiberoptic laryn-goscopy; difficult airway; awake intubation. [Respir Care 2014;59(6):865–880. © 2014 Daedalus Enter-prises]

Introduction

The transmission of a visual image through a flexiblefiberoptic bundle was first reported in 1954.1 Over a de-

cade later, an English anesthetist named Peter Murphyused a fiberoptic choledocoscope to aid in the nasal intu-

The authors are affiliated with the Department of Anesthesiology, Uni-versity of Virginia, Charlottesville, Virginia.

Dr Blank presented a version of this paper at the 52nd RESPIRATORY CARE

Journal Conference, “Adult Artificial Airways and Airway Adjuncts,”held June 14 and 15, 2013, in St Petersburg, Florida.

The authors have disclosed no conflicts of interest.

Correspondence: Stephen R Collins MD, Department of Anesthesiology,University of Virginia, PO Box 800710, Charlottesville, VA 22908. E-mail: [email protected].

DOI: 10.4187/respcare.03012

RESPIRATORY CARE • JUNE 2014 VOL 59 NO 6 865

bation of a patient with Still’s disease.2 Currently, fiber-optic intubation (FOI) with a flexible fiberoptic broncho-scope has become a mainstay of difficult airwaymanagement in awake, sedated, and anesthetized patients;its use is taught at the annual meeting of the AmericanSociety of Anesthesiologists (ASA),3 and its role is rec-ognized in guidelines for management of both anticipatedand unanticipated difficult airways.4-7

Fiberoptic Technology

The technology of fiberoptics is based on the opticalcharacteristics of very thin (diameter of 8–25 �m) flexibleglass fibers that are capable of transmitting light over theirlength. Insulation of these fibers by a glass layer with adifferent optical density enables transmission by internalreflection of light. An image is transmitted through thelength of the scope by an organized coherent bundle offibers that have the exact orientation at both ends of thescope. A separate fiberoptic bundle is attached to a lightsource to provide illumination, and lenses at the tip of thescope and eyepiece provide an image that can be focusedby the user. In brief, the fiberoptic bronchoscope consistsof an eyepiece atop a control handle with a focusing ringthat is attached to a thin flexible fiberscope. A thumbcontrol lever allows the distal tip of the scope to be flexedor extended. A separate port that travels the distance of thescope can be utilized for suction, injection of saline orlocal anesthetic, oxygen insufflation, or passage of brushesor forceps for diagnostic purposes.

A more recent evolution to the bronchoscope is theaddition of a charge-coupled device camera, whereby acaptured digital image is then transmitted electronically toan external monitor screen. More recent hybrid technologyretains fiberoptic bundles from the distal end of the scopeto the handle, where the charge-coupled device camera islocated. This configuration allows smaller external diam-eters of bronchoscopes with larger working channels andenhanced flexibility.

The components of the flexible fiberoptic bronchoscopehave been detailed well in prior reviews. Figures 1 and 2highlight basic components of a flexible bronchoscope.We refer the reader to one such comprehensive book chap-ter to explore these components in more detail.8 Rigid orsemirigid fiberscopes such as the Bonfils and UpsherScopehave also been described in successful management of thedifficult airway9,10 but are not discussed in this review.

Indications

Fiberoptic bronchoscopes are currently used to facilitateendotracheal intubation via either the nasal or oral route, inthe positioning of endotracheal and endobronchial tubesand bronchial blocking devices, and in airway examination

or evaluation. In clinical scenarios in which tracheal intu-bation is deemed necessary and mask or supraglottic ven-tilation (eg, via a laryngeal mask airway [LMA]) is un-likely to be successful or poses an aspiration risk, awakeFOI is a standard approach. FOI remains the acceptedstandard in elective airway management of the awake spon-taneously breathing patient with an anticipated difficultairway.11 FOI is ideally suited in such patients becauseintubation can be performed prior to the induction of gen-eral anesthesia with its attendant risks of inadequate ven-tilation and oxygenation, loss of upper airway patency,and failed intubation. This FOI technique also safeguardsagainst the risk of the cannot intubate/cannot ventilate sce-nario. Success of the technique, however, presupposes ad-equate time for preparation in a cooperative patient, arequirement for safe and successful FOI.

Table 1 lists common indications for awake FOI. Theneed for FOI may be anticipated based on a history ofdifficult intubation and various anatomic and anthropo-metric features that may predict difficult laryngoscopy.These include limited mouth opening, limited thyromentaldistance, reduced neck mobility, inability to prognath, oro-pharyngeal classification, and obesity.12 FOI may also beindicated for known or suspected cervical spine instability,anatomic malformations of the mandible or larynx, con-

Fig. 1. Flexible bronchoscope (Olympus LF-GP).

Fig. 2. Additional components of a flexible bronchoscope.

FIBEROPTIC INTUBATION

866 RESPIRATORY CARE • JUNE 2014 VOL 59 NO 6

genital deformities of the head and neck, and history ofhead, neck, and spine trauma. If a difficult airway is sus-pected, the ability to mask ventilate and the need for tra-cheal intubation should be assessed. Awake intubation isrecommended for patients who are at high risk for difficultmask ventilation, particularly those who may be at anelevated risk for aspiration during the airway managementprocess. While difficult airway guidelines are availablefrom a number of specialty societies, these are derived byexperts with analysis of limited randomized controlled tri-als; few recommendations have been validated rigorously.Familiarity, experience, and skill with different approaches,as well as equipment availability, must be considered whenapplying such guidelines to clinical practice.

During preoperative assessment, a detailed anesthetichistory may elicit a history of difficult or unsuccessfulattempts by direct laryngoscopy. Prior anesthetic recordsshould be obtained whenever possible. Multiple studies haveattempted to identify exam features or to define characteris-tics that predict difficult intubation. However, the reportedusefulness of such predictive tests has been questioned giventheir low positive predictive value.13 To complicate matters,the term “difficult intubation” has been variously defined inthe literature as limited view on direct laryngoscopy,12,14 theneed for more than one attempt or use of different airwayaids,15,16 and a quantitative score termed the Intubation Dif-ficulty Scale.17 These approaches limit the means of definingand assessing difficult intubation.

Nonetheless, a recent meta-analysis found that the over-all incidence of difficult intubation in subjects withoutpathologic airway anatomy was 5.8%.18 The incidence ofdifficult intubation in select groups such as those withabnormal anatomic features of the head, neck, or airway isdifficult to establish given that direct laryngoscopy is lesslikely to be performed in these patients. However, it islikely to be higher than in those subjects without airwayanatomic abnormalities. In an observational study, inde-pendent predictors of difficult/impossible mask ventilationand difficult intubation included limited mandibular pro-trusion, abnormal neck anatomy, sleep apnea or snoring,

and body mass index of 30 kg/m2 or greater.19 In a fol-low-up study, this same group reviewed over 50,000 an-esthetic records over a 4-year period and demonstratedimpossible mask ventilation as an infrequent event (0.15%);of this patient subset, 25% were difficult to intubate.20

Patients for whom FOI was planned were excluded fromdata collection and analysis.

FOI is often performed in patients with cervical spineinjury or instability. Although there are no outcome data tosupport a recommendation of FOI over other techniques insuch airway management scenarios, surveys of North Amer-ican anesthesiologists indicate that they prefer to use FOI inpatients with cervical spine injury. Interestingly, many alsoadmit limited skills with use of the fiberoptic bronchoscope.In one study of nearly 500 responses from 1,000 active mem-bers of the ASA who were surveyed, 78% reported a pref-erence for an awake intubation and use of a bronchoscope inpatients with cervical spine injury.21 A similar survey showedthat most respondents favored awake FOI in patients withcervical spine disease (ankylosing spondylitis or rheumatoidarthritis) presenting for elective surgery.22

It is important to note that FOI has not been provensuperior to other intubation techniques with regard to in-tubation success rates or clinical outcomes in patients withcervical spine injury, although studies on this subject tendto be limited by their retrospective nature and small sam-ple size.23 In one retrospective case control study exam-ining 454 subjects with critical cervical spine injuries overan 8 y period, a case group of 165 subjects required intu-bation within 2 months of injury due to the need for airwayprotection, respiratory failure, or provision of general an-esthesia.24 Of this subset, all subjects were intubated by anawake technique without the aid of general anesthesia ormuscle relaxants: 46% by fiberoptic laryngoscope, 32% byblind nasal intubation, and 22% by direct laryngoscopy.Despite a higher injury severity score in this case group of165 subjects, there was no difference in neurologic dete-rioration between this subset and those who were not in-tubated.

Despite the lack of unequivocal evidence demonstratingimproved neurologic outcomes in cervical spine injury pa-tients managed with an awake FOI technique, there arepurported advantages. All airway interventions, from maskventilation to direct or indirect laryngoscopy, result in somedegree of neck movement. This movement is typicallysmall, within physiologic ranges, and of unknown clinicalimportance. If performed, cervical in-line mobilization canprotect the cervical spine by diminishing such small move-ments regardless of airway technique. However, awakeFOI techniques in patients with injured cervical spinesmay have several benefits. First, the head and neck can bemaintained in a neutral position during airway manage-ment, and neck flexion and extension can be easily lim-ited. A previous study assessed cervical spine motion in

Table 1. Common Indications for Awake Fiberoptic Intubation

Known difficult intubationSuspected difficult intubation by direct laryngoscopy (eg, history of

difficult intubation, limited mouth opening, decreased thyromentaldistance)

Unstable cervical spineAbnormal anatomy

Congenital airway deformities (eg, Pierre Robin syndrome)Head and neck cancers (eg, supraglottic tumors)

TraumaFace/neckUpper airway



stable cervical spine subjects during intubation with aGlideScope video laryngoscope compared to a flexiblefiberoptic bronchoscope.25 The fiberoptic approach resultedin less cervical movement in the absence of cervical im-mobilization, a potential advantage not seen in a studycomparing a luminous stylet (Trachlight) to FOI in unsta-ble cervical spine subjects with manual in-line stabiliza-tion.26 A second benefit to awake FOI is that protectivereflexes can be maintained, thereby reducing the risk ofaspiration. Additionally, neurologic assessment can bemade after intubation and patient positioning and prior toinduction of a general anesthetic.

Fiberoptic bronchoscopy can also be used diagnosti-cally during and/or after FOI to facilitate inspection of theairway for the identification and diagnosis of airway traumathat may co-present in patients with head, neck, and cer-vical spine injuries. The use of techniques that do notpermit visualization of the lower airway in such cases maypredispose to incorrect endotracheal tube (ETT) placementvia a false lumen or through injured tissue, for example.Such conventional techniques may then lead to severe orcatastrophic complications, including massive subcutane-ous emphysema and airway loss. Sengupta et al27 reporteda patient with complete tracheal disruption after blunttrauma in which the injury was identified during an awakeFOI, facilitating precise ETT placement and positioning.Other reports have described soft tissue swelling and he-matoma causing airway obstruction in patients with cer-vical spine injuries.28,29 Fiberoptic techniques permit pre-cise evaluation of such pre-existing injury and can be usedto facilitate ETT placement beyond the level of injury. Forthese reasons, FOI in the spontaneously breathing patienthas been previously referred to as the method of choice forairway management in patients with airway trauma.30

Airway management challenges also exist in patientswith head and neck pathologies, a large category includingcongenital craniofacial defects such as micrognathia, headand neck cancers that may distort airway anatomy, surgi-cal scarring, and radiation fibrosis.Early studieshave shownthat the difficult airway resulting from head and neck pa-thology is a significant cause of deaths during generalanesthesia.31 Altered algorithms have been developed foruse in this population.32 Radiographic studies such as com-puted tomography and magnetic resonance imaging maybe particularly useful in airway evaluation of these pa-tients. During preoperative assessment, a history of hoarse-ness may indicate the location of a mass or progression ofdisease. Upper airway obstructive symptoms and signsshould be elicited. Positional dyspnea, specifically orthop-nea, is particularly worrisome. Furthermore, even with suc-cessful chemotherapy and radiation treatment in head andneck cancer patients, post-treatment changes can distortthe submandibular space and limit neck mobility, render-ing laryngoscopy difficult or impossible. In one recent

study of 152 difficult airway cases due to head and neckpathology, several factors that predicted airway difficultywere identified.33 These included cancer diagnosis, historyof radiation therapy, and supraglottic/glottic sites. Thosesubjects with glottic or subglottic lesions required the mostintubation attempts. Fiberoptic techniques may be ideallysuited for use in this patient subset. In this study, awakeFOI was performed successfully in 68 (44.7%) cases.33

The other most common airway techniques were inductionwith mask ventilation, followed by direct laryngoscopy(25%) and a dilator cricothyroidotomy technique (28.9%).Awake tracheostomy was performed in 1.3% of subjects.

Fiberoptic Techniques

FOI can be performed nasally or orally in awake pa-tients with topical or regional anesthesia alone, or in se-dated or anesthetized patients. The technique is most eas-ily performed with the patient supine or in the seatedposition. Standard airway and emergency equipment shouldbe available. In circumstances in which mask ventilationmay be difficult and risk of airway loss is high, an awaketechnique is preferred. A nasal approach is particularlyuseful in patients with a large tongue, limited mouth open-ing, receding lower jaw, or tracheal deviation or in cases inwhich an unobstructed surgical field is beneficial (eg, den-tal surgery). This approach is also anatomically favorablein that the laryngeal opening is more easily seen with thefiberscope as it courses past the nasopharynx with lessobstruction by the tongue.34

If performed orally, FOI may be facilitated by variousintubating airways or supraglottic devices. Such airwaysor devices allow the user to protect the bronchoscope,maintain a midline position, and displace the tongue moreeasily. Combination approaches utilizing supraglottic de-vices are discussed below. There are a variety of oral biteblocks and intubating airways available as well to facili-tate oral FOI. Unlike standard oral airways, these devicesutilize channels along their sides or top that permit themidline introduction and passage of a bronchoscope andETT. Proper placement prevents the base of the tongue orthe phalange of the airway from protruding into the pos-terior oropharynx and facilitates easy scope and tube pas-sage to the hypopharynx. One such common airway de-vice, the Ovassapian airway, is illustrated in Figure 3.

Other techniques to facilitate FOI include the jaw thrust,tongue protrusion, positioning the scope in the midline ofthe pharynx during advancement, and rotating the ETT90° counterclockwise if resistance is encountered duringadvancement to facilitate passage through the vocal cords.A laryngoscope blade can be used as an adjuvant to dis-place the tongue in order to promote bronchoscope andETT passage. Additionally, specialized face masks are



available that can deliver oxygen and permit mask venti-lation during FOI attempts (Fig. 4).

Patient Position and General Techniques

Awake FOI can be performed with the patient in theseated or supine position. When introducing the scope intothe patient’s mouth (oral approach), the tip of the scopeshould be tilted �45° (upward if intubating from the headof the bed or downward if intubating from the side of thebed or with the patient in a seated position) as shown inFigures 5 and 6. The tip of the scope is then advanced untilit is beyond the base of the tongue. A jaw thrust providedby an assistant can aid in bronchoscope passage through

the oropharynx. The tip can then be directed to the glotticopening. Fine adjustments with slight motion of the wristand elevation or depression of the tip using the angulation(thumb) control lever aid in steering the scope toward thevocal cords. Once the scope enters the trachea, it is ad-vanced to the level of the mid-trachea, where a previouslyloaded ETT is then guided into the trachea. The ETTshould be turned gently counterclockwise with retractionand then re-advanced if resistance is encountered duringplacement. This can decrease the likelihood of laryngealtrauma. Adequate size matching of the ETT on the scopepermits less play between the scope and tube and mayavoid the tube becoming caught at the level of the epiglot-tis or on the arytenoid cartilages (Fig. 7). In addition, thegreater the gap between the ETT and the bronchoscope,the higher the likelihood of failure of threading the tube.35

Once the ETT is passed, a bronchoscopic view can verifyplacement, with optimal tube positioning 2–3 cm abovethe carina in an adult patient. The scope is then withdrawnas the tube is held in place by hand. Finally, tube place-ment is checked by end-tidal carbon dioxide and auscul-tation and subsequently secured and connected to a circuitfor ventilation. For a nasal approach (see below), a vaso-constrictor can be applied to the preferred naris to limit orprevent bleeding during intubation. After slow dilation of

Fig. 5. The fiberoptic scope as introduced for an oral intubation.When introducing the scope from the head of the bed, the tip ofthe scope is angulated up at an angle of 45°.

Fig. 3. Ovassapian airway (Hudson RCI), one of several intubatingairways available to facilitate fiberoptic intubation via an oral ap-proach. The tip of the fiberoptic bronchoscope is shown followingthe plastic airway device, which helps guide the scope to theglottic opening.

Fig. 4. An endoscopy mask with a specialized central orifice forplacement of a fiberoptic bronchoscope. Note the additional (larger)port that can be connected to a circuit for mask ventilation.



the naris with increasingly sized nasopharyngeal airways,a well-lubricated ETT (usually 7.0 mm or smaller) is placedand gently pushed medially and posteriorly �6–8 cm withthe goal of advancing the tube into the posterior orophar-ynx. If resistance is encountered, caution should be exer-cised. If this problem occurs with both nares, the broncho-scope should be introduced first to assess for alteredanatomy (eg, nasal polyps) and also to direct passage aroundthe turbinates. With a firm jaw thrust by an assistant (al-ternatively, the tongue can be grasped and pulled forward),the bronchoscope is advanced and directed to the glotticopening for a view of the cords in similar fashion as withthe oral approach. Once past the cords, the ETT is ad-vanced to the level of the mid-trachea, and placement isconfirmed and finally secured.

Patient Preparation

In preparation for an awake FOI, the patient should bemade aware of the steps involved and reassured that pa-tient safety and comfort will be optimized. An antisiala-gogue is often used to decrease mucus and salivary secre-tions. Glycopyrrolate is frequently chosen (0.1–0.2 mgintravenously) because of a rapid onset and lack of seda-tion; however, atropine and scopolamine can also be used.For the nasal approach, the nasal mucosa (V1 and V2divisions of the trigeminal nerve) must be anesthetizedwith local anesthetic. Lidocaine is commonly used and istypically applied as a 2% gel or a 5% ointment. Solutionsof lidocaine can also be applied on pledgets or soakedcotton swabs and are usually combined with a vasocon-strictor (premixed solution of 0.25% phenylephrine and3% lidocaine) to limit bleeding by shrinking the nasalmucosal vasculature.

The selected nasal passage is then gently dilated withlubricated nasopharyngeal airways of increasing diameterprior to passing an ETT. For the tongue, oropharynx, and

larynx (V3 division of the trigeminal nerve and glosso-pharyngeal and vagus nerves), topicalization can beachieved by aerosolized, gargled, or nebulized lidocaine.Topical application of lidocaine during awake FOI ap-proaches reportedly results in plasma concentrations wellbelow toxic levels.36 Other common topical anestheticssuch as benzocaine have been shown to cause methemo-globinemia even in therapeutic doses, and Cetacaine (amixture of benzocaine and tetracaine) has a narrow ther-apeutic window.

These techniques and considerations for airway topical-ization have been described in detail in other reviews.37

The spray-as-you-go techniqueutilizes the fiberscopework-ing channel to directly administer local anesthetic to su-praglottic and glottic structures during advancement of theinstrument. This technique may minimize aspiration riskbecause airway reflexes are maintained until just beforepassage of an ETT. Supplemental oxygen can be deliveredby nasal cannula to reduce the risk of hypoxia duringsedation and intubation.

Fig. 6. When performing oral intubation when the patient is seatedor from the side of the bed, the tip of the scope is angulated downat an angle of 45°.

Fig. 7. Gap size differences between the fiberoptic bronchoscopeand a standard endotracheal tube (ETT) are shown. Poor sizematching with a large gap (at left) can result in the leading edge ofthe ETT contacting and becoming caught on glottic structures asit passes through the cords over the bronchoscope. Smaller gap(at right) reduces the risk of entrapment and trauma to the glotticstructures.



Regional Anesthesia

Regional airway blocks can be performed in preparationfor FOI in lieu of topical anesthetic approaches by theaforementioned methods. These include the glossopharyn-geal nerve block, superior laryngeal nerve block, and tr-anstracheal (transcricoid) block. The glossopharyngealnerve supplies sensory innervation to the posterior third ofthe tongue, the vallecula, the anterior surface of the epi-glottis, the walls of the pharynx, and the tonsils. Blockadeof this nerve can be performed using local anesthetic-soaked pledgets held at the base of the tonsillar pillars orby injecting local anesthetic using the mandible and mas-toid process as landmarks. The superior laryngeal nerve(branch of the vagus nerve) provides sensory innervationfrom the base of tongue and posterior surface of the epi-glottis to the arytenoids. It can be blocked by injectinglocal anesthetic using landmarks at the cornu of the hyoidbone. The transtracheal block is performed at the level ofthe cricothyroid membrane in order to anesthetize the va-gus nerve branches that supply sensory innervation to theunderside of the epiglottis and trachea.

Details of these blocks are provided in other reviews.37

They are typically performed based on clinician familiar-ity and experience as well as patient preference. A distinctadvantage of such blocks is a more rapid onset of localanesthetic action and a longer duration of action that mayfacilitate airway anesthesia with extubation. For instance,the duration of action of plain 1% lidocaine solution usedfor such specific nerve blocks is �75 min; it increases to400 min when 1/200,000 epinephrine is added to the so-lution.36 However, complications of airway blocks are notinsignificant and include intra-arterial injection, hematomaformation, and tracheal injury. Moreover, Sitzman et al38

have shown that glossopharyngeal nerve blocks are nomore effective than topical application of lidocaine as aroute of local anesthetic administration for awake directlaryngoscopy.

Sedation Versus General Anesthesia

Sedative medications and supplemental oxygen are of-ten administered in patients undergoing awake FOI. Goalsare to ensure patient comfort and to provide adequate anxi-olysis while maintaining a patent airway and ensuring ad-equate ventilation. In addition, patient responses to fiber-optic scope advancement and tracheal intubation can beblunted. Hypoxemia and aspiration are the most commoncomplications associated with awake FOI.39 During thistechnique, benzodiazepines are often combined with opi-oids to achieve adequate patient comfort and sedation.Midazolam is commonly used because of its rapid onset,short half-life, and ability to provide anterograde amnesia.Opioids such as fentanyl or morphine provide analgesia

and can depress laryngeal reflexes. However, they are as-sociated with respiratory depression. In an older studyusing volunteers, the combination of midazolam and fen-tanyl for sedation produced apnea in half of the subjects,with nearly all experiencing hypoxemia (oxyhemoglobinsaturation � 90%).40

More recent case reports,41,42 case series,43,44 and ran-domized studies45 have reported on dexmedetomidine forconscious sedation during awake FOI and its superior char-acteristics in this setting. Dexmedetomidine is a selective�2 adrenergic agonist with sympatholytic, analgesic, andsedative properties that does not cause respiratory depres-sion within recommended dosing ranges (0.2–0.7 �g/kg/h). Although studies are small and limited, it is an alternateand perhaps superior alternative for sedation of patientswith difficult airways during FOI attempts. Other studieshave reported similar results regarding patient comfort,sedation, and intubating conditions using a combination ofmidazolam and remifentanil for awake fiberoptic nasotra-cheal intubation.46 Still another study of 60 patients un-dergoing fiberoptic nasotracheal intubation found thatremifentanil facilitated better cooperation than propofol inpatients and may be safer when spontaneous ventilation iscritical.47

FOI can also be performed under general anesthesia,often in the spontaneously ventilating patient. There arefew studies investigating FOI in spontaneously ventilatinganesthetized patients. Propofol and sevoflurane have beencompared in this setting with little group differences ex-cept that patients receiving propofol had more frequentepisodes of hypoxemia.48 Easy and titratable anesthesiawas provided in both groups. Similar findings have beenreported in patients with anticipated difficult airways us-ing sevoflurane49 and propofol50 with the aid of pressuresupport ventilation. Another recent randomized study com-paring sevoflurane and propofol in patients scheduled formaxillofacial surgery who were difficult to intubate basedon predictive criteria reported a high intubation successrate with both.51 In this study, apnea was limited in bothgroups by the avoidance of opioids.

One might question whether awake FOI with topicalanesthesia solely might be a superior alternative in aneffort to reduce the risks of aspiration, airway compro-mise, inadequate ventilation, hypoxemia, and apnea asso-ciated with sedation or general anesthesia. However, therehave been some reports of upper airway obstruction usingtopical anesthesia approaches.52,53 One study has reportedthat awake FOI may be uncomfortable in 20% of patientseven with premedication and incremental sedation duringthe procedure with a benzodiazepine.54 Moreover, eventhe use of topical anesthesia combined with heavy seda-tion may be limited or may not prove adequate for somepatients, as seen in at least one case series.55 In selectpatient groups with difficult airways (children, uncooper-



ative adults, and patients with mental disabilities), generalanesthesia (via mask induction or intravenous titration)may be required.

Combined Techniques

The ASA practice guidelines for management of diffi-cult airways were developed in 1991. In 2003, revision ofthe guidelines included use of the LMA as a rescue devicefor ventilation and as a conduit for insertion of an ETT,either blindly or guided by a fiberoptic bronchoscope. Avariety of supraglottic airway devices are now available;these include the LMA Classic, LMA Unique, LMAProSeal, and LMA Supreme with slightly different fea-tures as well as the intubating LMA (ILMA) Fastrachspecifically designed for ETT placement. These supraglot-tic devices aid in displacing the tongue and epiglottis toallow glottic exposure that may not be achieved with con-ventional direct laryngoscopy in difficult airways. Theyalso assist in fiberoptic scope advancement since the ap-erture of a properly placed LMA lies in proximity to theglottis.56 As Table 2 highlights, ETT size is limited by thesize of an LMA conduit. Previous case reports havehighlighted the use of different supraglottic devices (Clas-sic,58,59 ProSeal,60-62 Supreme,63 I-Gel,64 and ILMA65) witha fiberoptic bronchoscope to facilitate successful intuba-tion.

Still other devices include rigid indirect laryngoscopessuch as the Airtraq, Pentax-AWS, and Bullard laryngo-scopes and video laryngoscopes such as the GlideScope.These devices can be used alone or in combination with afiberoptic bronchoscope to aid in intubation, as has beenreported in mannikin studies66 and case reports67-69 of dif-ficult airways. A unique advantage of FOI using a videolaryngoscope or a rigid/semirigid bronchoscope as an ad-juvant is that any ETT maneuvering can be performedunder direct vision, thereby limiting or avoiding trauma tothe glottic structures. Still other reports have describedmodified catheter-assisted techniques,70,71 the use of twobronchoscopes,72 and even novel devices (LMA CTrach)via fiberoptic bronchoscopy approaches.73

Outcomes/Comparison Studies

FOI has a unique role in several clinical scenarios whendifficulty with airway management is anticipated. Theseinclude intubation via an awake approach in the setting ofanticipated airway difficulty, intubation when neck motionis to be avoided, and evaluation of the airway (eg, trauma,inhalational injury). The value of FOI in the managementof the difficult airway is well established with a high suc-cess rate. In one early study of 423 consecutive fiberopticnasotracheal intubations spanning nearly 5 years, the suc-cess rate for intubation was 98.8%.74 The majority of intu-

bationswereperformedby trainees.Tenattemptswereabortedbecause narrow nasal passages did not allow easy passage ofa nasotracheal tube or fiberscope. Of the remaining (413)attempts, only 5 were unsuccessful, three of these because ofdifficulty with advancement of the ETT over the fiberscope.Sequelae were rare; inadequate topical anesthesia led to hy-peractive airway reflexes in 4.6% of patients but no perma-nent injuries. Complications of FOI approaches can be sig-nificant but are limited and are discussed below.

One of the first studies comparing FOI to another devicefor the management of the difficult airway (ILMA Fastrach)was performed in patients meeting difficult intubation criteriaunder general anesthesia.75 Surprisingly, more adverse eventsoccurred in the fiberoptic group, notably hypoxemia. How-ever, the randomized study found that the two approacheswere nearly equivalent and complementary; that is, when onetechnique failed, the other always succeeded. Failures of theILMA occurred in patients with head and neck cancers andprior cervical radiation therapy, suggesting that alignment ofthe ILMA with the glottis aperture may be difficult with thesepatient features and that FOI may be a better choice.

A similar study compared patients with predicted diffi-cult airways for awake FOI versus ILMA-guided trachealintubation under general anesthesia.76 Of note, exclusionsincluded poor mouth opening, cervical spine instability,morbid obesity, and pathologic airway abnormalities. In-tubation was successful in all patients in both groups, andthose in the ILMA group had higher satisfaction scores byquestionnaire. However, a second anesthesiologist wasneeded in 10% of the patients in the ILMA group forsuccessful intubation. This may reflect more limited ex-perience with the ILMA.

Another study of 54 patients comparing the ILMA andFOI (orotracheal) in awake patients with topical anesthesiademonstrated overall success rates of 84 and 96%, respec-tively; intubation times were shorter in the ILMA group,and cardiovascular responses were similar.77 A more re-cent study comparing FOI to the McGRATH video laryn-goscope in awake patients intubated under topical anes-thesia and sedation demonstrated no differences in time to

Table 2. Laryngeal Mask Airway Size and Endotracheal Tube ThatWill Fit Through the Device

LMA Size ETT International Diameter, mm

1 3.5 (uncuffed)2 4.5 (uncuffed)3 6.0 (cuffed)4 6.0 (cuffed)5 7.0 (cuffed)

Modified from Reference 57.LMA � laryngeal mask airwayETT � endotracheal tube



intubation, intubation success on the first attempt, and pa-tient-reported comfort with the procedure.78

Complications

There is a paucity of data on the specific incidence andscope of complications attributable to FOI. Potential com-plications associated with fiberoptic techniques include ep-istaxis (nasal approach), laryngotracheal trauma, laryngo-spasm, and aspiration of saliva, blood, or gastric contents.Most studies are in the form of case reports79-81 or smallprospective investigations examining injury.82 Presumablyrare complications include gastric distention and rupturefrom oxygen insufflation during FOI79 and the develop-ment of subcutaneous emphysema and pneumomediasti-num caused by tracheal perforation.80

A number of reports have focused on the mechanisms ofETT advancement during FOI because this process canfail or lead to traumatic laryngeal injury.83 Early reportsdescribed failure of ETT passage in up to 1% of attemptsrelated to inability to visualize the larynx, direct a tubetoward the larynx, or advance the tube over the fiberopticbronchoscope.74 A recent study of 45 patients undergoingclinically indicated (orotracheal) FOI demonstrated thattracheal intubation on the first attempt failed in 53.3% ofcases,82 a rate similar to those reported in other studies.84,85

Attempts were ultimately successful and were facilitatedby ETT maneuvers, notably tube retraction and 90° coun-terclockwise rotation. Using in vivo endoscopic visualiza-tion of the intubation process, this same study also dem-onstrated that the structure most frequently impinged uponduring attempted FOI was the right arytenoid cartilage.

The type, design, and flexibility of the ETT may be animportant factor in this regard. For instance, the rate offirst successful passage into the trachea during FOI hasbeen reported at 66% with a standard tube, 40% withwarmed standard tubes, and 40% with (flexible) wire-re-inforced tubes.85 Three cases of serious laryngeal injuryresulting from FOI with standard ETTs have been re-ported.81 It has been shown that impingement of the tubeon laryngeal structures decreases with use of a modifiedtip such as a tapered tip86 or Parker Flex-Tip87 ETT (Fig.8). The extent of the gap between the bronchoscope andthe tube also seems to be an important determinant in theprocess of tube placement as it advances over the scope.As highlighted earlier, a large gap can result in contactbetween the ETT bevel and laryngeal structures, increas-ing difficulty and the risk of injury.35 Using a smallerdiameter ETT or a larger diameter bronchoscope to min-imize this gap is generally recommended.

Training

Difficult airway management is a critical aspect of an-esthesiology and critical care practice, and the role of FOI

in difficult airway situations is well established. Moreover,skills in FOI are an essential part of anesthesiology train-ing. Arguably, the simulation and practice of crisis man-agement may be as important as technical skill learningwith any particular airway technique. Algorithms devel-oped for difficult airway management as well as preplannedstrategies may be most useful during such clinical scenar-ios. These include those developed by national societies aswell as institutional algorithms.88,89

However, instruction and training seem quite variableboth in simulated difficult airway scenarios and with spe-cific skill sets such as FOI. Although earlier studies dem-onstrated improved effectiveness with a stepwise trainingprogram (ie, learning fiberoptic techniques in a controlledenvironment: model or patient with a normal airway) com-pared to traditional teaching with difficult airway patients,90

it remains uncertain how best to facilitate skill develop-ment or to determine when an acceptable level of expertiseis reached. Once learned, the technique can then be incor-porated into routine anesthetic practice for continued pro-ficiency. There is evidence that the initial learning curvefor fiberoptic laryngoscopy and intubation is steep, and theskill is learned within 10 intubations in patients with normallaryngeal anatomy under general anesthesia.91 Studies of sim-ilar training programs with inexperienced residents haveshown that FOI training can be successfully and safely ac-

Fig. 8. A standard cuffed Parker Flex-Tip endotracheal tube. Notethe curved tapered distal tip designed to slide past the cords moreeasily and reduce trauma to glottic structures.



complished in anesthetized paralyzed (apneic) patients92 aswell as spontaneously breathing anesthetized patients.93 Oth-ers have argued that training devices94 and models37 can helpnovices better appreciate and learn technical skills involvedwith FOI.

Surveys

A survey of 132 American anesthesiology residencyprograms (60% response rate) found that only 33% of theprograms that responded had a difficult airway rotation,usually with formal instruction prior to the rotation.95 Thefiberoptic bronchoscope and LMA were the most frequentlyused devices in the rotations, with little emphasis on moreinvasive techniques. Another survey of American and Ca-nadian programs (60% response rate) reported similar re-sults with both formal and mannikin instruction in com-bination with formal airway rotations including the use offiberoptic techniques.96 Video laryngoscopes were alsohighly utilized.

Designated airway programs are also prevalent in inter-nal medicine-based critical care fellowship programs,97

with 58% of United States programs surveyed (66% re-sponse rate) reporting a formal rotation and 70% incorpo-rating simulation-based airway education. Fellows werereportedly taught FOI in 64% of programs. However, theaverage number of FOI procedures performed prior to grad-uation was estimated at � 10 in 65% of trainees. In asurvey of Canadian anesthesiologists, respondents (47%response rate) preferred the lighted stylet most often (45%)in a theoretical difficult intubation scenario, with only 26%preferring the fiberoptic bronchoscope.98 Expectedly, an-esthesiologists with experience in a given technique re-ported more comfort using it in patients.

United States Training

To our awareness, there is no consensus regarding thebest approach for teaching FOI. Although the ASA prac-tice guidelines include a number of airway adjuncts, in-cluding fiberoptic approaches to the difficult airway, theyprovide no specific guidelines for teaching these skills. Inaddition, a universally agreed upon airway managementskill set competency level has not been established, al-though one has been recommended in the Canadian sys-tem.99 Some have suggested that FOI is best accomplishedby those clinicians who use it in daily practice.89

In the United States, this subject is less well studied.Airway skills seem most often acquired in training pro-grams by way of formal airway management instructionwith varied use of simulation, mannikins, and anesthetizedpatients without predictors for difficult mask ventilation orintubation. Since the implementation of a task force of theSociety for Airway Management in 2008 and resurveying

of accredited anesthesiology residency programs in theUnited States, survey data reveal that there has been an in-crease in implemented specific airway rotations from 27% in1995100 to 33% in 200395 and to 49% in a more recent 2009survey.96 After direct laryngoscopy, the most common tech-niques for tracheal intubation were fiberoptic bronchoscopeand video laryngoscopy. In addition, simulation is now usedin 68% of reporting programs compared to just 12% in theaforementioned 2003 survey. Empirical data on trainee per-formance are needed before evidence-based airway manage-ment competency recommendations can be made.

Cadavers

Very limited data exist on the use of cadavers for airwayeducation and management, especially with regard to fi-beroptic techniques. Although cadaveric models have beenused for teaching of invasive procedures such as surgicalcricothyrotomy,101 their use has been controversial in theUnited States primarily because of ethical concerns.102,103

Some authors have suggested, however, that the use ofappropriately donated cadavers with educational workshoppermission may be a cost-effective method for educatingand training anesthesiology residents, especially comparedwith the high cost of mannikins and simulators.

It has been suggested that cadaveric models may in-crease the use of invasive airway techniques, including theuse of FOI in the management of difficult airway situa-tions.104 However, residents reported that they were nomore confident with FOI after the training in contrast toinvasive techniques such as cricothyrotomy, and the au-thors acknowledged that the use of unpreserved donatedcadavers would offer more realistic models for training.

Virtual Simulation and Model Fidelity

Simple models and mannikins have been used success-fully to teach FOI skills.90,105 These may be particularlyuseful to convey didactic information.105 The model meth-odology may improve FOI performance and be more prac-tical than hands-on practice with more traditional trainingwith anesthetized patients. Models may serve as an adjunctto FOI training in this regard by introducing and refiningkey fiberoptic manipulation skills.

More recently, simulation has been recognized as aneffective approach as well.106 Virtual-type simulators havethe ability to imitate a realistic clinical scenario better thanmany other approaches. In a recent observational study,residents were found to decrease the time required for FOIafter using a virtual reality simulator.107 Other studies haveshown that simulator practice can improve psychomotorskills for FOI.108

While studies on simulation training for FOI remainquite limited, this training modality arguably has the most



potential as an adjunct and substitute for clinical practicein FOI training and additionally provides the potential forobjective clinical assessment of trainee skill level and prog-ress. Whether practiced using simple models or performedin anesthetized patients, we believe that the use of a videomonitor for larger image display may be most effective forthe novice or trainee. This enables a more experiencedclinician to have the same view as the individual perform-ing the procedure and serves for real-time instruction, guid-ance, and evaluation.

Additional Uses

In addition to helping in intubation of the difficult air-way, fiberoptic bronchoscope techniques are useful in avariety of other settings. They are often needed for airwayexamination for diagnostic and therapeutic purposes inthoracic surgery. The fiberoptic bronchoscope is the ac-cepted standard for confirming ideal positioning of dou-ble-lumen ETTs and has led to an increased margin ofsafety with positioning of double-lumen tubes comparedwith auscultation and clamping maneuvers alone.109 Thefiberoptic bronchoscope helps with correct placement ofbronchial blockers (Fig. 9)110 and is essential for correct

positioning of single-lumen endobronchial tubes. Suchtechniques are particularly beneficial in the setting of adifficult airway and the need for lung isolation.111

While most of the available literature on the use of FOIin patients with difficult airways relates to predicted orknown difficulty associated with visualizing and accessingthe glottis and proximal trachea, another category of pa-tients with lower airway abnormalities may also benefitfrom or require FOI. It is important to remember that FOIremains the only airway management modality availableto date that is suitable for facilitating both endotrachealintubation and distal tracheal or endobronchial intubationunder direct visualization. Such maneuvers may be criticaland lifesaving in patients with tracheobronchial compro-mise from mediastinal masses or other pathologies. Directintubation of the distal trachea or even one main bronchusover an intubating bronchoscope may enable the skilled prac-titioner to bypass a life-threatening lower airway lesion orobstruction. Still other uses include placement of endobron-chial stents and exchange of airway guide-wire catheters.112

Finally, extubation strategies can be accomplished with fi-beroptic aid, specifically to assess pharyngeal airway swell-ing, vocal cord function, and subglottic stenosis by means ofadjuvants such as the LMA and airway exchange catheter, assuggested in a recent report.113

Summary

Management of the difficult airway is a crucial patientsafety issue, and FOI is a well-established and versatiletool for airway management in patients with known orsuspected difficult airways or as a rescue technique. Thetechnique may be performed in a variety of settings, in-cluding the operating room during anesthetic management,the emergency department, and the ICU. It is a componentof difficult airway algorithms and can be used in combi-nation with other airway devices such as the LMA andvideo laryngoscope to facilitate successful intubation. Avariety of clinical approaches are possible and includeawake nasal and oral approaches, typically with regionaland/or topical local anesthetic techniques with or withoutsedation. FOI is also possible in the anesthetized patient.Training is aided by models as well as the more recentadvent of virtual reality simulation.

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Fig. 9. The Arndt endobronchial blocker, one of the commerciallyavailable endobronchial blockers for lung isolation. At top, a fiber-optic scope is shown entering a bronchoscopy port of a multiportairway adapter. The endobronchial blocker (yellow) is passedthrough the blocker port. The bronchoscope can then be advancedinto and through a guide loop (shown at bottom), which can betightened and couples the endobronchial blocker to the broncho-scope. The bronchoscope is advanced through the endotrachealtube into the lung section to be blocked. The endobronchial bal-loon is inflated under bronchoscopic vision after the blocker isreleased from the bronchoscope and its position confirmed.



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Discussion

Berkow: I hear a lot from my resi-dents in my training program, as wellas feedback from other anesthesia res-idency programs, that the experienceof FOI [fiberoptic intubation] seemsto be decreasing now that we havevideo laryngoscopes and that a lot ofpatients who potentially in the past

would have been intubated fiberopti-cally awake are now having video la-ryngoscopy. And I even see this withmy surgical colleagues, who oftenwould ask for awake FOI for their cer-vical spine patients, now just ask forthe GlideScope. So, I’m concerned alot about that especially in the face ofcompetency and residency program re-quirements that are changing, and now

we are going to be required to monitormilestones and address competency ina more formal fashion. And I don’tknow how we make sure that our res-idents get that fiberoptic experiencethat they need.

Blank: I agree completely. As thesealternative technologies continue toevolve, they may ease the clinical chal-

FIBEROPTIC INTUBATION: AN OVERVIEW AND UPDATE


Hurford: One way we’ve gottenaround that in our anesthesiology train-ing program is that our first year res-idents do a month with our ENT [oto-laryngology] colleagues on the airwayservice. They go to the airway clinicand do a lot of nasopharyngeal exam-inations. They also go to the OR [op-erating room]and work with the ENTsurgeons. So, I must admit, at the endof that, they probably have a betterlevel of initial competency than manyof my attending physicians.

Ramachandran: I’d like to go backto Dr Berkow’s comment. I think thechallenge with all of these advancedairway techniques is the failure rate.There is no single technique thatdoesn’t have a failure rate that’s trulystartling if you look at the statistics. Afailure rate of 10–15% hasn’t reallychanged for the awake FOI technique.It’s scary if that’s our final sort of endpoint for airway management.Granted, the risk of the actual numberof cases where you would be in a sit-uation of failed intubation, failed su-praglottic airway, and failed fiberop-tic is going to be very small. Perhapsthe changing technology means thatthere needs to be a change, a para-digm shift, in what we think is ourultimate best technique. To commenton a point made in an earlier discus-sion, I’d like to emphasize the pointthat the best techniques are the onesyou know and know well. Thoseshould be your plan A and your planB. I find that FOI teaching is verybiased toward one thing or the other;it’s not a wide range of things thatwe’re used to. And what Dr Berkowsaid is particularly important becausemany soft indications for awake FOImeant that the art of the fiberoptic washow you got the sedation right; youjust don’t get that chance anymore.Our residents go to the ENT clinic,but I think oral FOIs are still a hugechallenge to train young residents on.

Collins: I am impressed with eventhe most recent (revised) practice

guidelines1 for management of the dif-ficult airway by one main point. De-spite the structured guidelines, in thecase of unsuccessful intubation afterinduction of general anesthesia withadequate face mask ventilation, thereare such a variety of options. The air-way approach at this point is up to theclinician. In fact, one can try any num-ber of options. I think, practically, thepoint is really to use what one is goodat using in terms of managing the air-way based on one’s judgment and ex-perience within that clinical situation.I am not aware of resident trainingrequirements for how many success-ful intubating LMA [laryngeal maskairway] placements are needed beforeone graduates a program. Or success-ful light wand attempts, or fiberopticintubations, etc. I do believe residencyprograms are graduating residents whoare not capable of meeting some or alot of the proficiency standards forthese tools. And perhaps we shouldn’tfocus on learning them all, but ratheron learning a few of them and thenlearning how to decide which ones areadvantageous in different scenarios.

Blank: I think the point in that slide isthat the chosen modality is not as im-portant as learning to use it well. This isa point we’ve heard several times al-ready. I think this is true, and what wasdemonstrated in one of the studies high-lighted that the failure rate was muchlower than 10%. Now, this was per-formed by very experienced anesthesi-ologists, who have extensive experiencewith these procedures, and their failurerate was 6/12,000. That is an impres-sively low failure rate. That clearly isnot the case in all the reported studies,but his approach was to simply use 2modalities instead of 12 or 15 and to bevery good at them. I think it’s possibleto achieve a lower failure rate, but thenthe other challenge Dr Berkow and DrCollins pointed out is how do we trainour residents to use all of them? Weneed to establish minimum standards forour training programs. One thing I sawthat was disturbing in reviewing this lit-

erature was that in internal medicine–based fellowship programs in criticalcare, approximately two thirds of thegraduating fellows had done fewer than10 FOIs. I don’t think any of us reallythink that competency or expertise canbe developed with those kinds of num-bers. Certainly not in patients who re-ally need that approach–patients with adifficult airway. I think it is importantto train residents to perform flexible fi-beroptic intubation and other selectedapproaches to airway management elec-tively in healthy patients with normalairways, and that’s certainly what wetry to do. But we don’t focus on 12different modalities.

Berkow: It’s interesting that in themost recent survey by Pott2 that youcited, what’s startling is that the sur-vey found that still only 50% of an-esthesia residency programs have aformal airway rotation. So, if we don’teven have formal airway rotations, Idon’t know how we can guarantee thatour residents get trained on these de-vices. And I hope that will change nowthat we’ll have to show milestones.We’re currently working in our de-partment to make milestones for air-way management and airway tech-niques; it’s a big challenge, and insome ways, there are so many differ-ent techniques to teach, how do youteach them all within the span of oneresidency period?

Ramachandran: To follow up onthat, in thinking about the hospitalmodel for management of failed air-way, Dr Napolitano, could you com-ment on whether fellows now in sur-gery or intensive care are required todo a minimum number of emergenttracheostomies?

Napolitano: Yes, that’s an interest-ing question. The Accreditation Coun-cil for Graduate Medical Education(ACGME) modified the program re-quirements for graduate medical edu-cation in pulmonary disease and crit-ical care medicine3 in September 2012



and suggested that pulmonary medi-cine critical care fellows should haveexperience in percutaneous tracheos-tomy. It’s always been mandatory forsurgical critical care, so it’s alwaysbeen part of the critical care fellow-ship training for surgery. We were abit miffed when the guidelines cameout for medicine because there wereno recommendations of having sur-gery backup and who’s going to trainthem . . . the exact same issues relatedto how to become competent in thisprocedure. But, we recognized it wasimportant, and so we partnered withour pulmonary medicine colleagues,and we taught their attending staff first.They became experienced, and it’s justlike doing a difficult airway; onceyou’re experienced, then you can teachyour trainees. But it’s the exact samething. We have moved now to bothbronchoscopy and tracheostomy sim-ulation in order to start to begin to getcompetency. And of course, the hu-man experience is very valuable.

Blank: Is that simulation on manni-kins or cadavers, or both?

Napolitano: Both. And we have, aspart of ACLS [Advanced Cardiovas-cular Life Support], procedure issuesthat are done but we can teach trachthe same time that we teach cricoid.

So, it’s simple; it’s all about doing itthe same way every time.

Berkow: There’s a relatively newsimulator developed by my friend andcolleague Dr Paul Baker in New Zea-land called the Orsim. He developedan airway simulation program becausehe really felt that the current simula-tions that are out there or simulated ona mannikin really didn’t accurately re-flect an actual FOI in a human being.So, there are efforts underway to makeFOI simulation much more useful foranesthesiologists.

Blank: What kind of additions hashe added to the experience?

Berkow: It includes a bronchoscopeand a laptop with a graphics simula-tion which looks much more realisticthan some of the older ones. It offersmultiple airway scenarios and pathol-ogies; plus it’s portable, so you cantake it with you from place to place.

Durbin: Continuing with changingtechnology, and being one of the olderteachers in the room, new technolo-gies create a significant challenge foracademic faculty. I’m happy teachingFOI, but it is more of a challenge forme to teach video laryngoscopy be-cause I haven’t actually had enoughhands-on experience yet. I’ve watched

50 or more intubations, I think I knowwhat the residents are doing right andwrong, but the reality is that I don’tdo many cases myself, and learning touse these devices competently requireshands-on experience. So, as the tech-nology advances and these changes oc-cur, we also need to ask, “what do wedo about the person who’s in practicenow, and how do we get them to adoptnew technology and become compe-tent?” This same question needs to beapplied to academic faculty. We needa solution for “how to teach the teach-ers” when new technology is intro-duced into clinical practice.

REFERENCES

1. Apfelbaum JL, Hagberg CA, Caplan RA,Blitt CD, Connis RT, Nickinovich DG, etal. Practice guidelines for management ofthe difficult airway: an updated report bythe American Society of AnesthesiologistsTask Force on management of the difficultairway. Anesthesiology 2013;118(2):251-270.

2. Pott LM, Randel GI, Straker T, Becker KD,Cooper RM. A survey of airway trainingamong U.S. and Canadian anesthesiologyprograms. J Clin Anesth 2011;23(1):15-26.

3. Accreditation Council for Graduate Medi-cal Education (ACGME). ACGME pro-gram requirements for graduate medical ed-ucation in pulmonary disease and criticalcare medicine (internal medicine). Ap-proved September 2012; effective July2013. http://www.acgme.org/acgmeweb/Portals/0/PFAssets/2013-PR-FAQ-PIF/156_pulmonary_critical_care_int_med_07132013.pdf. Accessed March 4, 2014.

This article is approved for Continuing Respiratory Care Educationcredit. For information and to obtain your CRCE

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